Synthetic resin and process of making same



messed Mar. s, 1935 I 1,993,700

' UNITED STATES PATENT OFFICE SYNTHETIC ansnt AND Paocnss or MAKING seamLloyd 0. swollen and Kenneth M. Irey, Terre Hante, Ind., assignors toCommercial Solvents Corporation, Terre Haute, Ind., a corporation ofMaryland No Drawing. Application February 24 1931 Serial- No. 518,027

Ourinvention relates to certain new compositinued. The products obtainedin such cases tions of matter which are valuable as components aregenerally of much higher acidity and difier of cellulose estercompositions, molding commark dly from he P d ts Obtained by thepositions, lacquers, and varnishes. proved p oce herein described- 5These new compositions are obtained by th It is believed t in 8 thermalP 5 esterification or polybasic acids, or their anhyllet hereindiseleeed nd m d he 17 11711 8 drides, with both polyhydric andmonohydric altypes of compounds are produced:

cohols, giving esterified structures oi high molec- 0H ular weight, say500 or higher. 10 Our invention contemplates the production'oi Q m atnesterified structure of low acidity in which, on

i is bell s I I of the p lg li yd in l l l of i r groups representsmlyhydric R on hydric alcohol, and A(COOH)= a polybasic acid.

provement of the process and composition depolybgsic ifii b fi fl if 15scribed in a copending application, U. S. Serial reacted w h as a eamoun o e m I c No 515 396 med February 12 1931 by w G alcohol, eitherin the presence or absence of an Arem f .l of producugg resins, ie'sterification catalyst, gives among other comv is an improvement overUnited States Patent pounds mixture of compounds commune ap- Ourinvention relates specifically to an im- 1,938,791 by w. c. Arsem forComposition. of Parent" mainly so matter and process for making same,issued A December 12, 1933. According to the disclosures 1 therein made,a polyhydric alcohol is first re- 0H acted with a polybasic acid or itsanhydride. A and 28 part, but not all, of the carboxyl groups in theproduct thus obtained are then esterified, in the presence 01' anesteriflcation catalyst of the usual Q type, with a monohydric alcohol.The compound thus produced is next further condensed F The product ofthe step described above,

by heating relatively few being esterified with a monohydric alcohol,gives groups remain unreacted. We have now found ainly mjxt unds r thatthe resinous product obtained by the pro- $53329 m a m of compo cedurejust described may be very materially o-oo-a-coon' improved bysubjecting it to an additional treats ment which serves to removecertain of the ma- Q 35 terials produced during the operation and which,OH ii. allowed to remain in the resin, give the prodand o uct propertiesrendering it much less suitable for many more purposes than is the casewith 12-01;

4 the improved product which we obtain. We v 40 I have now found that bytreating with a suitable solvent, for example, petroleum hydrocarbon, Itshould be noted also that in addition to the the product obtained asabove described, certain products described above, the product containsL undesirable by-products may be removed thereconsiderable amounts ofunchanged products of 5 from so as to give a much more desirable prodthefirst stage andcertain other products or much uct. 1 lower molecular'weight and boiling point, ior 11, instead of following the procedureset forth example, simple esters of the polybasic acids, are above, thepolyhydric alcohol, monohydric alcoalso produced, which, unless removed,reduce to hol and polybasic acid or its anhydride are an appreciableextent the desirable p operties of simply mixed together and heated, thereaction these new materials when used as resins.

takes a diiierent course and does not give the After removing the excess01' monohydric alcodesired product. The same is true it the acid, holused in the second stage of the process-the or its anhydride is firstreacted with a monoreaction product is heated in order to causerurhydric alcohol and a polyhydric alcohol then ther esterification.During this operation, ap-

a added to the mixture and the reaction conpatently the chief reactiontakes place between I a the products of the second step mentioned aboveand the unchanged product of the first step in such a manner as toproduce a mixture of compoimds of the type:

where .n may be any number but is usually between 1 and 4. Theproportion of reactants and the method of procedure may be varied so asto change the average value of n in the above formula and, therefore,the properties of the final product. For example, in order to increasethe number n, the proportion oi. polyhydric alcohol should be increased,in which case the' proportion oi monohydric. alcohol is necessarilydecreased somewhat. n

- The example given below will illustrate the preparation of our newcompositiom Reaction product of glycerol, butyi alcohol.

' Dhtha1,ic acid-(anhydride) v acid (sp. gr. 1.2), and the'resultingliquid heated as quickly as possible-to about C. in a vessel providedwith a fractionating column. The material is then distilled at such arate that the temperature of the liquid being heated rises from 110 C.to C. in about 1 hour and 25 minutes.

- the heating condensation occurs with The unreacted butyl alcoholremaining in the product is then removed by distilling to 125 C. liquidtemperature in vacuo. In this step apparently from one-half totwo-thirds of the free carboxyl groups remaining after the first step ofthe operation are esterlfled with butyl alcohol.

The product obtained by the above containing iree hydroxyl and carboxylheated at a temperature-oi to procedure,

C. for .10

to 30 hours, or until the acid value, as determined in acetone solution,is less than about 12. During the elimination of water, and the productbecomes more and more viscous, while the acid value continues to falluntil in the later stages of the condensation the product becomes almostsolid.

According to our improved procedure, the prod-' uct producedashereinabove set forth, is next agitated with an equal or larger portionof a suitable solvent, ior example, petroleum hydrocarbon having aboiling range between 95 and 160 C., at atemperature above 90 C. forfrom about onehalf to aboutthree, hours. The petroleum'hydrocarbon,or'other solvent,'layer is then decanted and the extraction rep ted fromtwo to three times with iresh portions oi solvent. This treat-- mentextracts almost completely the 'dibutyl phthalate which is formed duringthe process as a by-product and which renders the resin product softerthan is usually desirable. when the extraction operation has leumhydrocarbon remaining in the resin maybe removed by distilling toaliquid temperature of ample, the proportion of perature. when heated tothey become viscous liquids.

normal butyl alcohol mixed with 22 grams -of concentrated hydrochloricgroups, is

, glycol,

been-completed the petrophthalic anhydride and the 120 C. in vacuo. Theresulting product is a plastic solid slightly deformable at roomtemperature. For convenience of handling the resin may be dissolved in asolvent composed of 9 parts toluol and 1 part n-butyl alcohol. Ifdesired,

' the resin may also be treated in solution with Noritol or other suchagent and then filtered so as to decolorize the resin.

In the specific example described above for the purpose of illustratingour invention, we have used 1 mole of polyhydric alcohol and 1.5 molesof polybasic acid. It should be understood, however, that the relativeamounts of these materials used may-be varied somewhat without alteringappreciably the course of the reaction. For exacid t0v p ly dric alcoholmay be varied between 1 /4 and 2 moles. It should be noted also that anappreciable excess of monohydric alcohol was added to the reactionmixture, a portion of which was removed unchanged; Usually the amount ofthis constituent 'entering into the reaction variesfroni about /4 "moleto about ly moles..

The compositions ob range in consistency from slightly deformable solids,at ordinary room tema higher temperature exceptions, be de c b d s asic, flexible, fusible resins. They have high molecular weightsranging.usually;between 'wo'and .2000, and are practicallynon-volatileat temperatures below 200 C. They are immiscible withpetroleumhydrocarbons, miscible with esters, ketones and aromatichydrocarbons and alcoh ls hen mixed in equal in all proportions inproportions, and are soluble the above-mentioned solvents. in thin filmsby the evaporation of a solvent they give flexible coatings, which areimproved by the presence of a certain proportion of a substance such asnitrocellulose or cellulose acetate.

above 4 ry viscous liquidsto v They may, with few acetone and'inmixtures of .alcoholsand any of when deposited These substances arecompatible with the constituents-of lacquers and exert on nitrocelluloseand cellulose acetate compositions a plasticizing action and increasethe flexibility ofthe film. They combine the properties of ordinaryresins.

Quite awide variety of stitu'ted with satisfactory results for thedifferent materials used in the specific example cited above. In placeof .phthalicanhydrlde, for example, dior polybasic acids as phthalicacid, terephthalio acid, tartaric acid, malic acid," succinic acid andcitric acid maybe employed. other ,dior .polyhydric glycol, butyleneglycol, rythrltoL niannitol etc.

may besatisfactorily substituted. Instead t1 nor mal butyl alcohol otheraliphatic orv aromatic alcohols such as, ior'example, ethanol, secondarybutyl alcohols, benzyl alcohol, normalamyl alcohol, methyl alcohol, theethyl ether of ethylene the mono acetate of diethylene glycol or thelike may be used. Obviously, however, varyingthe constituents of thereaction mixture varies the character of the product formed and to someextent the operating procedure which must be followed in order .toobtain the desired prode Among others, the following combinations havegiven very satisfactory results: (1:). glycerol,

ethyl ether ofethylone; slycohib) glycerol, phthalic a dride andplasticizers and materials may be subsuch- For the glycerol alcoholssuchasethylene benzyl alcohol, (0) glycerol, succinic acid and amylalcohol. 7

It isunderstood, of course, that we make no claim to either thecomposition or the procedure set forth in said United States patentapplication Serial No. 515,396, filed February 12, 1931 by W. C. Arsem,or the said United States Patent,1,938,'791 by W. C. Arsem. We desire toclaim only the improved products and process hereinabove described byus;

It is understood also that we are not limited to the use of petroleumhydrocarbons boiling be-' tween 95 and 160 C. but may also employ anyother solvent which is a non-solvent for the resin ous materials beingtreated but which is a solvent for the polybasic acid ester which-it isdesired to remove, and provided said solvent does not boil at atemperature sufliciently high to prevent its separation from the resinby distillation or other means. Due to the wide range of materials whichmay be reacted according to the present invention it is obvious that thesolvent material suitable for use in any particular case will dependupon the particular materials being reacted, and hence the solubility ofthe final resin and of the polybasic acid ester which it is desired toseparate from it,

As previously indicated, in preparing our new compositions either apolybasic acid or its corresponding anhydride may be employed. In theappended claims, therefore, it is understood that the term polybasicacid includes also the corresponding polybasic acid anhydride.

What we desire to claim is:

1. In a process for the production of a non-volatile plastic fusibleresinous condensation prod not by heating one mol of polyhydric' alcoholwith from 1% to 2 mols of a dibasic carboxylic acid, eflectingsubstantial but not complete esterification of the resulting productwitha monohydric alcohol in the presence of an esterification catalyst,removing the water of reaction and the excess monohydric alcohol, andfurther heating to effect condensation by reaction between the remainingfree carboxyl and hydroxyl groups, the improvement which comprisesextracting from said final product the esters of .the polybasic acidwith the monohydric alcohol formed as a byproduct.

2. In a process for the production of a nonvolatile plastic fusibleresinous condensation product by heating one mol of glycerol with from1% to2 mols of a dibasic carboxylic acid, efiecting substantial but notcomplete esterification of the resulting product with a monohydricalcohol in the presence of an esterification catalyst, removing thewater of reaction and the excess monohydric alcohol, and further heatingto effect condensation' by reaction between the remainingfree carboxyland hydroxyl groups, the improvement which comprises extracting-fromsaid final product the esters of the polybasic acid with the monohydricalcohol formed as a by-product.

3. In a process for the production of a nonvolatile plastic fusibleresinous condensation product by heating one mol of glycerol with from1% to -2 mols of phthalic acid, effecting substantial but not completeesterification of the resulting product with a monohydric alcohol in thepresence of an esterification catalyst, removing the. water of reactionand the excess monohydric alcohol, and further heating to effectcondensation by reaction between the remaining free carboxyl andhydroxyl groups, the improvement which comprises extracting from saidfinal product the esters of phthalic acid with the monohydric alcohol.

4. In a process for the production of a non-volatile plastic fusibleresinous condensation product by heating one mol of glycerol with from1% to 2 mols of phthalic acid, effecting substantial but I ,not completeesterification of the resulting product with butyl alcohol in thepresence of an esteriflcation catalyst, removing the water of reactionand the excess butyl alcohol, and further heating to effect condensationby reaction between the remaining free carboxyl and hydroxyl groups, theimprovement which comprises extracting from said final product thedibutyl phthalate formed as a by-product.

5. In a process for the production of a non-volatile plastic fusibleresinous condensation product by heating one mol of glycerol with from1% to 2 mols of phthalic acid, effecting substantial but not completeesterification of the resulting product with butyl alcohol in thepresence of an esterification catalyst, removing the water of reactionand the excess butyl alcohol, and further heating .to effectcondensation by reaction between the remaining free carboxyl. andhydroxyl groups, the improvement which comprises ex tracting from saidfinal product, by means of a liquid petroleum hydrocarbon boilingbetween 95 and 160 C., the dibutyl phthalate formed as a by-product.

LLOYD C. SWALLEN. KENNETH M. IREY.

